Continuous COD Monitoring Helps Swiss Brewery Optimize Biogas Production

Turning Wastewater into Renewable Energy

Biogas reactors are used within wastewater treatment to reduce the volume of organic waste and produce biogas. Through a process known as anaerobic digestion (AD), microorganisms are used to break down organic matter in the absence of oxygen.

In brewery operations, this means that industrial wastewater—rich in sugars, starches and other brewing byproducts—can be treated while simultaneously generating a methane-rich gas that serves as a renewable energy source.

Key benefits of this process include:

• Waste reduction: Significantly less sludge is sent to landfill, lowering greenhouse gas emissions and creating the potential for nutrient-rich fertilizer.
• Renewable energy generation: The captured biogas provides heat and electricity, reducing dependence on fossil fuels and cutting CO₂ emissions.
• Cost savings: Producing energy onsite and minimizing sludge disposal lowers operating costs and improves overall efficiency.

By transforming wastewater into a valuable resource, biogas reactors help breweries meet environmental goals while lowering both carbon emissions and operating costs.

Importance of Organics Monitoring for Biogas Production

For the anaerobic digestion process to be successful, the organic load of the industrial wastewater must be carefully monitored. Effluent from the brewing process often contains fluctuating levels of sugars, starches, alcohol and suspended solids from grain and yeast—variations that directly affect how efficiently microorganisms can produce biogas.

To maintain stable conditions, plant operators measure biochemical oxygen demand (BOD) and, even more importantly, chemical oxygen demand (COD). Tracking COD before the wastewater reaches the reactor allows them to spot issues early. Excessive COD levels can lead to imbalances in the anaerobic digestion process, inhibit microbial activity and reduce biogas production, while an unexpected drop may signal dilution or other imbalances that require quick attention.

Monitoring COD levels provides valuable insights into the organic load of the wastewater, allowing system operators to proactively manage and adjust the process for maximum biogas production.

Real-Time COD Monitoring Solution for Brewery Wastewater

To safeguard reactor performance, the brewery required a solution to measure COD levels within their industrial wastewater plant, with monitoring required at two key points within the process: 

1. Reactor inlet: Monitoring the pollutant load before digestion ensures the organic content remains within safe limits. Excess COD can overwhelm the biogas reactor, disrupting operations and risking an unplanned shutdown.

2. Plant outlet: COD monitoring at the discharge point confirms treated effluent meets municipal regulations, protecting the environment and avoiding costly fines.

Working alongside experts from Badger Meter, plant operators at the brewery chose to install the i::scan spectrophotometer Probe at both measuring points. As a part of the Badger Meter BlueEdge™ portfolio, this advanced solution delivers continuous, real-time COD data, giving operators clear insight into the organic load to keep the plant running smoothly.

The probe is designed for effortless installation and requires no consumables or moving parts, making it simple to operate and maintain. It can be inserted directly into the media or mounted within a flow cell, providing accurate, stable performance over an extended lifetime and delivering exceptional return on investment.

Measurable Impact

By implementing an advanced monitoring system from the BlueEdge™ solution portfolio, the brewery now has complete visibility into the organic load of its industrial wastewater and can quickly assess how efficiently the treatment process is performing. Maintenance is minimal—routine cleaning takes only minutes and requires no shutdown—allowing operations to run without interruption.

Continuous monitoring ensures that any spike in organic load is identified early and addressed before it can impact biogas production. With this assurance, the brewery can consistently hit production targets, protect the local environment and strengthen its commitment to sustainable operations. The project highlights how modern water-quality technology can turn a sustainability philosophy into everyday practice.